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%I #5 Mar 31 2012 12:36:20
%S 1,99,12721,1903102,312841383,54811120355,10054355708671,
%T 1909325866644096,372521441486934113,74275858248868186497,
%U 15075586701977689855707,3105668779830679872107622
%N Number of permutations of n copies of 1..5 introduced in order 1..5 with no element equal to another within a distance of 2
%H R. H. Hardin, <a href="/A190921/b190921.txt">Table of n, a(n) for n = 1..47</a>
%e Some solutions for n=2
%e ..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1
%e ..2....2....2....2....2....2....2....2....2....2....2....2....2....2....2....2
%e ..3....3....3....3....3....3....3....3....3....3....3....3....3....3....3....3
%e ..4....4....4....4....4....4....4....4....4....4....4....1....4....4....4....1
%e ..5....2....2....5....5....5....5....1....5....5....1....4....1....1....2....4
%e ..1....3....5....3....2....2....3....5....3....2....3....5....5....5....5....5
%e ..4....5....3....4....4....1....4....3....2....3....5....3....2....3....3....2
%e ..2....4....4....2....3....5....5....4....4....4....2....4....4....4....1....4
%e ..3....1....5....5....5....4....2....2....5....1....4....2....5....5....5....3
%e ..5....5....1....1....1....3....1....5....1....5....5....5....3....2....4....5
%K nonn
%O 1,2
%A _R. H. Hardin_ May 23 2011